1. Technical Field
The present invention relates to a rotary input apparatus.
2. Description of the Related Art
In general, a mobile terminal has the numbers 0-9 and the symbols * and # on a keypad of 12 keys. In addition to the numbers, there are also alphabet letters as well as consonants and vowels of Korean letters marked on such a keypad, to enable the input of information including numbers and letters. Recently, there are also navigation keys formed above the keypad equipped with a variety of functions such as phone number search, writing and managing text messages, and connecting to the Internet, etc. There are various forms of navigation keys, such as button types and rotary types, etc., but the use of rotary input apparatus is currently increasing, as they enable various functions such as menu browsing, etc.
Rotary input apparatus are used in televisions, camcorders, and PDA's (personal digital assistants), etc., as input apparatus in the form of rotary switches, rotary encoders, and rotary volume dials, etc.
In such rotary input apparatus, rotating by a particular angle can transfer a certain degree of vibration periodically via the user's hand, etc., and the sensation of this vibration is referred to as a click sensation. Clicks transfer a certain vibration to the user, at the rotation of a rotary input apparatus, thereby allowing the user to recognize whether or not a rotation has been made on the rotary input apparatus and to recognize the rotation angle, etc. Thus, click sensations not only increase the convenience of using a rotary input apparatus, but also allow the user to operate the rotary input apparatus more precisely.
An example of a conventional rotary input apparatus that generates click sensations include, first, a rotary input apparatus for generating click sensations consisting of a rotary member having a plurality of concavo-convex portions, a click member for engagement with and disengagement from the concavo-convex portions, a biasing member for urging the click member elastically in a direction towards the concavo-convex portions, and a holding member for holding the biasing member.
A second example includes a rotary input apparatus consisting of a rotor capable of free rotational motion, cam seats provided in the rotor and having concavo-convex portions, clicking members to be put in slide contact with the cam seats, and a holding member to hold the clicking members, where the holding member is furnished with a plurality of holding parts for holding the clicking members. There are a plurality of different concavo-convex portions formed so that different clicking sensations are obtained when the cam seats are in sliding contact with the clicking members.
Such conventional rotary input apparatus for generating click sensations have grooves such as the concavo-convex portions or the cam seats, where click sensations are created when click members are caught on and disengaged from these grooves. However, in rotary input apparatus thus comprised, the fact that click sensations are created even when they are not desired by the user presents an inconvenience in usage. Also, since click sensations are created as the click members are caught on and disengaged from concavo-convex portions or cam seats of constant sizes, the magnitude of the click sensations cannot be regulated.
Further, in conventional rotary input apparatus, because the click members are caught on and disengaged from concavo-convex portions or cam seats, not only is there a problem of damage on the click members due to friction, etc., but also the composition is made complicated, due to the requirement of a flat spring, etc., for providing elastic force by which the click members always press against the cam seats or concavo-convex portions.